Thermocouple



T. G. COGHLAN.

THERMOCOUPLE.

APPLICATION FILED MAR. 9. 1921.

mmm;

Patented July 11, 1922.

PATENT OFFICE.

THOMAS G. COG-ELAN, 0F WELLSBURG, WEST VIRGINIA.

THERMOCOUPLE.

Application filed March 9, 1921.

To all whom t may con/cem: v

Be it known that I, THOMAS G. COGHLAN, a citizen of the United States, residing at Wellsburg, in the county of Brooke and State of West Virginia, have invented certain Improvements in Thermocouples, of

lwhich the following is a specification.

This invention is an improved thermocouplel designed for combination with an internal combustion engine and mechanism adaptedto indicate the temperature of combustion and to provide the necessary information for regulating the constituents of the explosive mixture.

The present invention is an improvement of the apparatus shown in the U. S. patent to Hopkins, No. 903090, and its characteristic features of improvement comprise means for preventing the couple from igniting the explosive charge in the combustion chamber of the engine.

The invention is characterized, in its preferred form, by a metal housing or tube adapted to be set in the wal-l of an explosion chamber, insulating means housed by the metal tube, conductors of diii'erent metals passing through the insulation to a union or junction in a chamber within the housing, and a meter in circuit wit-h the conductors for indicating or interpolating the temperature within the explosion chamber.

My improved device possesses the desiderata` that it can be mechanically secured advantageously in gas tight and insulated relation to the combustion chamber of an engine with the union of the conductors housed therein so as to prevent the ignition of the charge thereby as also the deposit of carbon thereon by the burning gases, and that will cause an instant indication of -the slightest temperature changes in the -gases so as to prematurely ignite succeeding charges of combustible gas and has been subject to deposits of carbon interfering with its desired operation, which objection- Specification of Letters Patent.

Patented July 11, 1922.

Serial No. 451.025.

able conditions are avoided by my improvements.

In the accompanying drawings, Fig. 1 is a broken View o f a form of .my improved device applied to the combustion chamber o f a as engine shown in fragmentary section; 1g. 2 is a longitudinal sectional view of the features embodying my improvements' taken on the line X- X of Fig, 1; Fig. 3 is a sectional view taken on the line 3"- X of Fig. 2, and Fig. 4 is a sectional view taken, on the line 1X-4X of Fig. l2.

My improved mechanism, in the form thereof illustrated in the drawings, comprises the metal housing l, which is suitably a steel tube having a threaded end la, an enlarged threaded end ,1b and polygonal flange 1c adjacent to the latter end, the tube containing the cylindrical bore 1d having the enlarged section 1e within the end 1*.

An insulating core 2, containin the longitudinal passages 2a, fits within t e housing, the core having the enlarged end section or head 2b which fits within the housing section 1e, andthe opposite end of the core terminating short of the corresponding end of the housing to provide therein a recess or chamber 1f, say l inch in diameter..

Conductors 3, respectively of diierent metals such as chroma'l (nickel plus 5% chromium) and alumal, (nickel plus 10% aluminum), extend through the passages 2a and have a union or junction 3 within the chamber 1f. The conductors 3, at the end of the core 2 opposite the chamber 1f, extend through passages 4 in an insulating washer 4 and through the exible armor 5 fixed to the housing 1 and the armo-r 6, fixed to the milli-volt meter 7 to the binding posts 8 in the back of the meter, the latter being adapted for fastening to a convenient support as the dash board of an automobile.

The armor 5 is provided with an end flange 5a which engages the washer 4 and is engaged by the ange 9 of a gland nut 9 screwed on the housing section l", whereby the parts 1, 2, 4 and 5 are clamped together.

The housing 1 is adapted to be connected with a gas engine 10 having the combustion chamber 10a and the Water cooling chamber 10b by tapping the wall 10 of the cooling chamber with the threaded aperture 10d, adapted for engaging the threaded end 1 of the housing, and the wall 10's with the larger threaded aperture 10t in line with the aperture 10d. An externally threaded bushing 11, having the polygonal section 11aL together with the internally threaded stuing chamber .11", and the externally threaded gland or follower 12 having the polygonal section 12a, are sleeved on the housing 1. The housing 1 is. assed through the aperture 10t and its en la screwed into the aperture 10d, the bushing 11 is screwed into the aperture 10f, and the follower 12 is screwed into the bushing against the packing 13 therein to rovide a gas tight joint with the housing. R`he washer 4,:which is pressed against the ends of theparts 1b and 2b, prevents the escape of gas from the cylinder 10 between these parts. Thefdevice is thus adapted to be connected with the cylinder in gas tight relation.

It will be understood that temperature changes in the combustion chamber will be indicated l-by the milli-volt meter due to variations in the electrical action induced by .heating the union of the conductors to different temperatures.

As the union 3ELV of the couple is housed in the chamber'lf and as this chamber is filled with inert or dead gas resulting from the explosions of the live gases, such live gases are. not in direct or such contact with the union as to bel ignited thereby.

There is thus provided, by the metal tube and porcelain or insulating core, housing means for the conductors and a cell for the union withinthe housing means, of such character as to permit such union to be directly heated by the exploded charge and to prevent the ignition by such heated union of a succeeding charge of explosive fluid.

Having thus described my invention, I claim:-

1. A thermo-couple comprising diferent metals forming a union and means com prising an open chamber for housing said union so as to permit its exposure to heat transfer from gaseous products of combustion and prevent its ignition of an unexploded fluid adapted for providing such gaseous products.

2. A thermo-couple comprising conductors of different kinds forming a union and housing means for said conductors, said housing means comprising a metal tube having therein an open chamber containing said union and adapted for preventing the explosion by heat tmnsfer therefrom of an explosive uid with which'said chamber communicates.

3. In a thermo-couple, the combination with an insulator and a housing therefor, said housing having an open chamber, of conductors extending through said insulator and having a union within said chamber.

4. In a thermo-couple, the combination with a metal .tube and an insulating core housed therein, said tube and core forming an open chamber, of conductors extending through said core to a union of dissimilar metals within said chamber.

5. A thermo-couple comprising a pair of conductors of dissimilar metals having a union and a housing for said conductors, said housing having a restricted open chamber in an end thereof with said union therein adjacent to the opening thereof.

6. In a thermo-couple, the combination with an engine having an explosion chamber, of a housing set in a wall of said chamber, an insulator within said housing, and conductors extending through said insulator to a union in communication with said chamber, said housing and insulator providing a cell for said union and adapted for preventing the explosion of gas in said chamber thereby.

7. A thermo-couple comprising a metal tube having an enlarged end, an insulating core disposed in said tube, said core having an enlarged end in the enlarged end of said tube, `means comprising a coupling member whereby said tube and core are held in fixed relation, and conductors extending throu h said core to a union in a cell at the end o said core, opposite said head.

8. A thermo-couple comprising a metal tube provided with means adapted for connecting it with a gas chamber and packing means movable on said tube for preventing the escape ofluid around the same, in combination with an insulating core in said tube and forming therewith a cell communicating with said chamber, means for closing the joint between said tube and core to prevent the escape of gas therebetween, and conductors extending through said core to a union in said chamber.

In testimony whereof I have hereunto set my name this seventh day of March, 1921.

THOS G. COGHLAN. 

